This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. xc2xa7119 from my application FLAT TYPE COLOR CRT filed with the Korean Industrial Property Office on Nov. 10, 1999 and there duly assigned Ser. No. 49714/1999.
1. Technical Field
The present invention relates to a flat type color cathode ray tube (CRT), and more particularly, to a flat type color CRT in which the pitch of a tie bar of a shadow mask is formed to be greater than or equal to the pitch of the black matrix formed on a fluorescent film of a panel.
2. Related Art
In a color cathode ray tube (CRT), an electron beam emitted from an electron gun passes through an electron beam passing hole of a shadow mask having a color selection function and lands on a fluorescent film formed on a surface of a screen of a panel. Thus, a fluorescent substance coated on the fluorescent film is excited and an image is formed. With a recent trend toward making a flat surface of a screen, a shadow mask installed in the cathode ray tube must be made flat compared to a convex surface of the non-flat one. As a doming phenomenon, the deformation of the shadow mask occurs due to heat during operation, it is not easy to manufacture a flat shadow mask.
I have found that it can be difficult to design and manufacture an improved high quality flat color cathode ray tube. Efforts have been made to improve a black matrix layer, a shadow mask, and a flat cathode ray tube display.
Exemplars of recent efforts in the art include U.S. Pat. No. 4,915,658 to Lopata et al., entitled REFERENCE AND SUPPORT SYSTEM FOR FLAT CRT TENSION MASK, issued on Apr. 10, 1990, U.S. Pat. No. 5,939,842 to Beeteson et al., entitled SELF STABILIZING ELECTRON SOURCE FOR FLAT PANEL CRT DISPLAYS, issued on Aug. 17, 1999, U.S. Pat. No. 5,745,168 to Ninomiya, entitled HOLE-SIZE MEASURING SYSTEM FOR CRT BLACK MATRIX LAYER, issued on Apr. 28, 1998, U.S. Pat. No. 5,725,787 to Curtin et al., entitled FABRICATION OF LIGHT-EMITTING DEVICE WITH RAISED BLACK MATRIX FOR USE IN OPTICAL DEVICES SUCH AS FLAT-PANEL CATHODE-RAY TUBES, issued on Mar. 10, 1998, U.S. Pat. No. 5,576,596 to Curtin et al., entitled OPTICAL DEVICES SUCH AS FLAT-PANEL CATHODE RAY TUBE, HAVING RAISED BLACK MATRIX, issued on Nov. 19, 1996, U.S. Pat. No. 5,477,105 to Curtin et al., entitled STRUCTURE OF LIGHT-EMITTING DEVICE WITH RAISED BLACK MATRIX FOR USE IN OPTICAL DEVICES SUCH AS FLAT-PANEL CATHODE-RAY TUBES, issued on Dec. 19, 1995, U.S. Pat. No. 5,363,011 to Fendley, entitled STRIP-TYPE SHADOW MASK EFFECTIVE TO ALLEVIATE DEGROUPING, issued on Nov. 8, 1994, U.S. Pat. No. 6,140,754 to Ko, entitled STRUCTURE OF SHADOW MASK FOR FLAT CATHODE RAY TUBE, issued on Oct. 31, 2000, U.S. Pat. No. 5,169,351 to Choi, entitled SHADOW MASK HEATING APPARATUS FOR COLOR CRT OF THE FLAT FACEPLATE TYPE, issued on Dec. 8, 1992, U.S. Pat. No. 5,145,432 to Midland et al., entitled OPTICAL INTERPROGATION SYSTEM FOR USE IN CONSTRUCTING FLAT TENSION SHADOW MASK CRTS, issued on Sep. 8, 1992, and U.S. Pat. No. 4,794,299 to Chiodi et al., entitled FLAT TENSION MASK COLOR CRT FRONT ASSEMBLY WITH IMPROVED MASK FOR DEGROUPING ERROR COMPENSATION, issued on Dec. 27, 1988.
While these recent efforts provide advantages, I note that they fail to adequately provide an improved flat type color cathode ray tube.
To solve the above problems and others, it is an objective of the present invention to provide a flat type color cathode ray tube having improved visual recognition.
It is another objective of the present invention to provide a flat type color cathode ray tube in which the pitches of the tie bar of the shadow mask and the black matrix of the fluorescent film are changed.
Accordingly, to achieve the above objectives and others, there is provided a flat type color cathode ray tube including a bulb consisting of a flat type panel where a fluorescent film on which inner surface a fluorescent pattern and black matrix are coated is formed, and a funnel extended from the panel, and a frame assembly having a flat type shadow mask installed adjacent to the panel in the bulb and having a plurality of strips for forming a plurality of slits and a tie bar for connecting neighboring strips, in which a vertical pitch of the black matrix formed on the fluorescent film is less than or equal to a vertical pitch of the tie bar of the flat type shadow mask.
It is preferred in the present invention that the vertical pitch of the black matrix of the fluorescent film is formed between 0.3 mm through 1.9 mm. Also, it is preferred in the present invention that the vertical pitch of the black matrix of the fluorescent film is formed between 0.4 mm through 1.5 mm.
Also, it is preferred in the present invention that the vertical pitch of the tie bar of the flat type shadow mask is an integer multiple of the vertical pitch of the black matrix of the fluorescent film.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides an apparatus, comprising: a display unit conveying varying visual images to a user; a fluorescent film being formed on a surface of said display unit, said fluorescent film having fluorescent patterns; a black matrix being coated on said fluorescent film between said fluorescent patterns; a mask being mounted adjacent to said display unit, said mask forming at least one tie bar, a plurality of slits, and a plurality of adjacent strips, said strips being disposed between said slits, said at least one tie bar connecting said adjacent strips, a first pitch of said black matrix and a second pitch of said at least one tie bar forming a predetermined ratio; and a light source emitting light through at least one of said slits to said display unit to form the images at said display unit.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides a flat type color cathode ray tube display apparatus, comprising: a flat type color cathode ray tube; a flat type panel being located at a front region of said flat type color cathode ray tube; fluorescent patterns being formed on an inner surface of said panel; a black matrix being applied on said inner surface of said panel between said fluorescent patterns; a flat type shadow mask being mounted adjacent to said panel, said mask forming at least one tie bar, a plurality of slits, and a plurality of adjacent strips, said strips being disposed between said slits, said at least one tie bar connecting said adjacent strips, a first measurement of said black matrix and a second measurement of said at least one tie bar forming a predetermined ratio; and an electron source emitting an electron beam passing through at least one of said slits of said mask to said panel to form an image, said mask being disposed between said electron source and said panel.
To achieve these and other objects in accordance with the principles of the present invention, as embodied and broadly described, the present invention provides a method, comprising: forming a fluorescent film on a surface of a display unit, said fluorescent film having fluorescent patterns; applying a black matrix onto said fluorescent film between said fluorescent patterns; placing a mask at a location adjacent to said display unit, said mask forming at least one tie bar, a plurality of slits, and a plurality of adjacent strips, said strips being disposed between said slits, said at least one tie bar connecting said adjacent strips, a first pitch of said black matrix and a second pitch of said at least one tie bar forming a predetermined ratio; and emitting light through at least one of said slits to said display unit to form an image at said display unit.
The present invention is more specifically described in the following paragraphs by reference to the drawings attached only by way of example. Other advantages and features will become apparent from the following description and from the claims.